Abstract

The aim of this thesis was to explore if, and then how, electric cars and buses can contribute to sustainable personal mobility. Electric vehicles have increasingly been seen as a potential sustainable solution for the transport sector due to their high energy efficiency, close to zero emissions in the use phase, and the possibility to be powered by electricity from renewable resources. However, there are concerns about future scarcity of resources (e.g. lithium and cobalt for batteries), vehicle range, costs, high energy use in the production of batteries, as well as insufficient scientific support for how electric vehicles could be a part of a transition towards sustainability regarding personal mobility.   The challenges for a fast transition towards sustainability are large and many. The transport sector is not contributing to such development, mainly due to emissions, use of fossil energy, and use of materials mined and recycled under unacceptable conditions. Furthermore, existing societal goals (e.g. fossil-fuel independent vehicle fleet by 2030 in Sweden, UN Agenda 2030, and the Paris agreement) are insufficient for sustainability and are not complemented by concrete plans or an approach for how to engage stakeholders and achieve coordinated actions for sustainability. The Framework for Strategic Sustainable Development includes a principled definition of sustainability that is necessary and sufficient for sustainability and procedural support for collaborative innovation for a strategic transition to fulfillment of that definition, which is why it has been used as an overarching methodology in this thesis.  The research verified through several studies conditions for how electric vehicles can play a vital role in a strategic transition of personal mobility towards sustainability. Through stakeholder collaboration (e.g. interviews and workshops), a vision for sustainable transport with a focus on electric vehicles and an initial development plan towards that vision were designed. Several life cycle focused studies investigated (through calculations and data collection from literature, life cycle databases, interviews and workshops) about environmental and social impacts and costs for electric cars and buses. The stakeholder collaboration, combined with conceptual modelling, also resulted in models for generic support for multi-stakeholder collaboration and planning for strategic sustainable development of transport systems and communities, and for how to include electric buses in the procurement model of public transport. The strategic sustainable development perspective of this thesis broadens the analysis beyond the more common focus on climate change issues and should be able to reduce the risk of sub-optimizations in community and transport system development when applied in that context. The generic support for multi-stakeholder collaboration could potentially also promote a more participatory democratic approach to community development, grounded in a scientific foundation. "p"Contact the author to receive a pdf of the full thesis (papers included): sven.boren@bth.se or telephone +46455385723.

Abstract

Electric vehicles can play an important role in a future sustainable road transport system and many Swedish politicians would like to see them implemented faster. This is likely desirable to reach the target of a fossil independent vehicle fleet in Sweden by 2030 and a greenhouse gas neutral Swedish society no later than 2050. However, to reach both these targets, and certainly to support the full scope of sustainability, it is important to consider the whole life-cycle of the vehicles and also the interaction between the transport sector and other sectors. So far, there are no plans for transitions towards a sustainable transport system applying a sufficiently wide systems perspective, in Sweden or elsewhere. This implies a great risk for sub-optimizations. The overall aim of this work is to elaborate methodological support for development of sustainable personal road transport systems that is informed by a strategic sustainable development perspective. The Framework for Strategic Sustainable Development (FSSD) is used as a foundation for the work to ensure a sufficiently wide systems perspective and coordinated collaboration across disciplines and sectors, both in the research and application. Maxwell’s Qualitative Research Design and the Design Research Methodology are used as overall guides for the research approach. Specific research methods and techniques include literature studies, action research seminars, interviews, and measurements of energy use, costs, and noise. Moreover, a case study on the conditions for a breakthrough for vehicles in southeast Sweden has been used as a test and development platform. Specific results include a preliminary vision for electrical vehicles in southeast Sweden, framed by the principled sustainability definition of the FSSD, an assessment of the current reality in relation to that vision, and proposed solutions to bridge the gap, organized into a preliminary roadmap. The studies show that electric vehicles have several sustainability advantages even when their whole life-cycle is considered, provided that they are charged with electricity from new renewable sources. Electrical vehicles also imply a low total cost of ownership and could promote new local ‘green jobs’ under certain conditions. Particularly promising results are seen for electric buses in public transport. As a general result, partly based on the experiences from the specific case, a generic community planning process model is proposed and its usefulness for sustainable transport system development is discussed. The strategic sustainable development perspective of this thesis broadens the analysis beyond the more common focus on climate change issues and reduces the risk of sub-optimizations in community and transport system development. The generic support for multi-stakeholder collaboration could potentially also promote a more participatory democratic approach to community development, grounded in a scientific foundation. Future research will explore specific decision support systems for sustainable transport development based on the generic planning process model. GreenCharge

Abstract

Composite repair systems are used for many years to restore locally the pipe strength where it has been affected by damage such as wall thickness reduction due to corrosion, dent, lamination or cracks."/jats:p" "jats:p"Composite repair systems are commonly qualified, designed and installed according to ASME PCC2 code or ISO 24817 standard requirements. In both of these codes, the Maximum Allowable Working Pressure (MAWP) of the damaged section must be determined to design the composite repair. To do so, codes such as ASME B31G for example for corrosion, are used. The composite repair systems is designed to “bridge the gap” between the MAWP of the damaged pipe and the original design pressure."/jats:p" "jats:p"The main weakness of available approaches is their applicability to combined loading conditions and various types of defects. The objective of this work is to set-up a “universal” methodology to design the composite repair by finite element calculations with directly taking into consideration the loading conditions and the influence of the defect on pipe strength (whatever its geometry and type)."/jats:p" "jats:p"First a program of mechanical tests is defined to allow determining all the composite properties necessary to run the finite elements calculations. It consists in compression and tensile tests in various directions to account for the composite anisotropy and of Arcan tests to determine steel to composite interface behaviors in tension and shear. In parallel, a full scale burst test is performed on a repaired pipe section where a local wall thinning is previously machined. For this test, the composite repair was designed according to ISO 24817."/jats:p" "jats:p"Then, a finite element model integrating damaged pipe and composite repair system is built. It allowed simulating the test, comparing the results with experiments and validating damage models implemented to capture the various possible types of failures. In addition, sensitivity analysis considering composite properties variations evidenced by experiments are run."/jats:p" "jats:p"The composite behavior considered in this study is not time dependent. No degradation of the composite material strength due to ageing is taking into account. The roadmap for the next steps of this work is to clearly identify the ageing mechanisms, to perform tests in relevant conditions and to introduce ageing effects in the design process (and in particular in the composite constitutive laws).

Abstract

This paper presents a microscopic traffic model for the validation of advanced driver assistance systems. This model describes single-lane traffic and is calibrated with data from a field operational test. To illustrate the use of the model, a Monte Carlo simulation of single-lane traffic scenarios is executed with application to cooperative adaptive cruise control system. The model is then validated by comparing the simulation results with data gathered from test drives. ©2007 IEEE.

Abstract

International audience; The resolution of conflicts between n aircraft is highly combinational and cannot be optimally solved using classical mathematical optimization techniques. Using a priority order to solve a n-aircraft conflict is much easier but the solution is not optimal. FACES (free-flight autonomous coordinated en route solver) is a model for coordinated on-board sequential conflict solving. In this project, conflict-free trajectories are obtained by applying elementary maneuvers to each aircraft, sequentially, according to some priority order. In this paper, a comparative study on a set of proposed priority heuristics to provide a suitable priority order is presented, and aggregated heuristics are compared according to some criteria. The conflict solver FACES using heuristics is tested in en-route upper airspace within an air traffic simulator using real traffic data.

Abstract

The development of Electric Vehicles (EV's), either fully electric (BEV…battery electric vehicle) or different hybrids (like HEV… hybrid electric vehicles or PHEV…plug-in hybrids), is an undeniable prerequisite to fulfill the worldwide emission targets for transport even within the next 10-15 years. The conventional development methods and tools on the other hand, are so far only optimized for the development of vehicles with ICE engines only and not well designed to develop EV's at all. To close this gap, the research in ASTERICS is focused on simulation and testing methods as well as tools that enable the optimal, cost efficient and safe development of EV's. Realistic driving cycles for e-vehicles, models for e-components, test procedures, test equipment and tools as well as system simulation and evaluation have been investigated in, which lasted 3 years (Oct. 2012 – Sept. 2015) and involved 10 partners (OEM: CRV, Volvo; Supplier: AVL, Siemens SAS/SISW, Thien eDrives, GustavKlein; Research: see above).

Abstract

Obtaining a representative loading spectrum that corresponds well to the reality is still one of the greatest challenges for fatigue life calculations and optimal design of the trailer body. A good qualitative and quantitative knowledge of the spectrum leads to more efficient usage of material, a better design of connection points and an overall decrease of the weight of the trailer, which finally results in a significant decrease in the price of a ton of cargo per km. Despite that, the approach is nowadays mostly based on the experience and rules of thumb. It typically results in over-dimensioning of some parts while other parts remain vulnerable to failure due to unknown loading patterns. This paper describes a generic approach to solve the problems mentioned above applied in a research project named FORWARD (Fuel Optimized trailer Referring to Well Assessed Realistic Design loads). The project lasted two years and was carried out in cooperation with several different trailer manufacturers and 1st tier suppliers. The loading history of more than 1000 hours for five trailer types were captured in the shape of strains, accelerations and velocities of various elements of the trailers, enabling reconstruction of the loading in terms of forces and moments acting on the wheels and kingpin. Parallel to this extensive test-campaign, a novel generic physics-based computational approach was developed to predict selected loads encountered during common manoeuvres to all trailer types. The computational approach was validated against test-data and resulted in creating a generic multibody library applicable for all trailer types, and an automated post-processing routine for the large amount of test-data. First Published Online: 16 Dec 2014 Document type: Article

Abstract

A hailstorm has heavily damaged a glass fibre mesh reinforced mineral render of an externally insulated composite system (ETICS) of a family house. While a neighbouring house of identical design and of the same age showed only minor defects, for the house under investigation it was a total failure of the render. Material probes were taken from the damaged façade and analysed physically and chemically. Before renovation, the hail resistance of the façade was determined with a unique artificial hail impact test method: Clear ice balls were shot against the façade with the help of a launcher, where the kinetic energy of the projectile can precisely be controlled. The type of damage due to natural hail could be reproduced. The impact energy needed to cause a damage similar to the one caused by the natural hail was determined. The hail impact damage was also identical to results from hail testing performed in the laboratory on similar systems. Since the amount of rendering material on the façade was not according to standards of the Swiss Society of Engineers and Architects - it was by far too thin - specific laboratory tests were performed with specimens not only made of similar materials but also with a comparable thin render layer. By systematic variation of the projectile size and its velocity, the impact parameters were studied and correlated to the type and extent of the hail impact damage. A threshold, associated with the first appearance of full circle cracks in the render, was found to be a kinetic energy of 2.5 J. The assessment of a supposed thickness effect and an effect of doubling the reinforcement on the hail impact resistance and the effect of the age of the façade however was a challenge. The methodological limitations given by the circumstances and the approach used are discussed in this paper.